[Mud-n-Beer]

I've been using Autolite Platiums for 20 years, and they last for a long, long, long time. Also have been using Autolite Plug Wires too for 20 years.

I do however pull my plugs out every once in a while just to check em out, regap them, if needed, and might hit them with a small wire brush.

I'll never buy any one elses junk. One auto parts store that I deal with, says the plug wires are cheap, but they have always done me good. Why change a good thing? The price is right too!!!!!!!!!!!!!!!!!

[Mud-n-Beer]

Originally Posted by brendanc

Libertys might not be the most popular jeep for trail riding because of the IFS, but I try anyway...

That said, I need to replace my spark plugs and I was looking for the best spark plugs I can get. Whatever came with my jeep are still in there at 55k and I am starting to feel the engine not running as smooth as it used to.

I read through the thread and you guys seem to like Champion... but should I go with Platinum or Iridium? There is a $6, Iridiums being more expensive. Thoughts?

Any other tips would be appreciated, I want to get the job done well and right the first time.

Edit: Also, I am getting many mixed results as to the gapping for my vehicle? The spark plugs say do 0.035, under the hood says 0.040, and haynes manual says 0.045? What gives? Who should I listen to?

About the plug gap, set them by what the label under the hood says. Those Haynes Manuals suck, and are not always perfect.

[brendanc]

Good to know. I went ahead and ordered the champion 9002's (iridium) so we will see how they do. As far as i can tell the wires dont need to be replaced.

[98junk]

Originally Posted by Mud-n-Beer

About the plug gap, set them by what the label under the hood says. Those Haynes Manuals suck, and are not always perfect.

The FSM for 97 sez .035

[ZJ5point2GCL]

Originally Posted by mniemela

I could be wrong, but I've been told that platinum plugs are not supposed to be installed in chrysler vehicles. When my dad put the platinums in his cherokee, it was a huge mistake and he went back to the regular copper; and it runs well now. It also depends on what works with your jeep. Experiment!!!

Thats what i heard too, when i went to the parts store i wanted so bosh +4s or some e3's but he said to use only champion or ngk's on mopars and pretty much any domestic v8, asked my mechanic and he agreed, so i have some champions in there now.

[silentknight]

has anyone tried the new pulstar pulse-plug?...

[purplepig]

it really just depend on the motor. NGK's ran great in my Honda car and motorcycle, but I only use Champion in a jeep.

[rezamesa]

bosch is garbage, NGK iridium in the best!

[CB3]

I cannot say which is the best, but for a 4L I'm pretty sure NGK are the best, or among the best.

In my 96 XJ I had the stock plugs, whatever they were, and they were OK. Then I tried NGK and they were fantastic. Then I tried Bosch's best and they sucked badly, with much less lowend torque.

In my 2006 LJ I went from whatever the stock one's were (Champion I think?) to NGK and it is a noticeable improvement, running more smoothly at idle, much better lowend torque and slightly better mid-rpm torque. No difference at high rpm. Also, the NGK seem to get slightly better gas mileage.

In both my Jeeps I used and use NGK copper plugs, not their fancy platinum ones. Not sure how the NGK platinum would do, but their copper sure are great.

The Bosch platinum were terrible in my 4L Jeep engine.

FYI - I've heard from several people, including mechanics, that Bosch plugs are great in European cars (and possibly Japanese cars), but Bosche are NOT good in American cars. I don't know if that's true in general, but my two 4L Jeeps sure prefer NGK over anything else I've tried, and the one 4L Jeep I tried the Bocshe in hated them.

For a 4L engine, IME: NGK cooper are great, not sure about NGK platinum or Iridium (but I'd like to explore/try those). Boshe Platinum are terrible (in the 4L engine). The stock plugs (Champion I think) were were OK performers.

I have no experience with other brands of plugs.

[CB3]

I like Autolite Platinum in my Old 98 (model year 94) because my mechanic recommended them. They work great.

But would Autolite be good in a 4L Jeep? I don't know.

[Fun2Jeep]

Is there a big difference between the Autolite APP985's and the AP985's? Double vs. single platinum?

[epic05]

As much distaste I have for crapion plugs I must say that they do the best job in Chrysler products with standard ignition

[r12b12]

The Best is e3 Spark Plugs....You will notice the difference.

[03WJDave]

The WJ had NGK's in it when I bought it. Pulled them out and was amazed what bad shape they were in. I stick with plain old Champion Coppers and never had a problem.

[tjkj2002]

Originally Posted by r12b12

The Best is e3 Spark Plugs....You will notice the difference.

The only thing you will notice is a lighter wallet and many misfires down the road.